Gripper.



B. sTIeGIN s.

GRIPPER. v APPLIQATION FILED JULY 29, N09.

Batented Apr; 5; 1910.-

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STATES PArnuT OFFICE.

Wm A. STIGGINB, OI BEVERLY, HASBAGHUSETTS, ABBIGNOB '10 UNITED SHOE RAGRINERY COKPANY, OF PATEBSON, NEW JERSEY, A CORPORATION OI NEW GBIPPER.

JERSEY.

Specification of Letters Patent.

Patented Apr. 5, 1910.

Application filed July 29, 1908. Serial No. 610,236.

To all whom it may concern:

Be it known that I, EDWARD A. Srrroems, a citizen of the United States, residing at Beverly, in the county of Essex and State of Massachusetts. have invented certain Imrovements in Grippers, of which the folowing description, in connection with the accompanying drawings, is a specification, like reference characters on the drawings indicating like parts in the several figures.

This invention relates to grippers and particularly to the grippers of shoe lastmg and other upper ul-hng machines.

The inventlon as for its object to provide a gripper mechanism comprising a single, strong and compact construction having a small number of parts which are so formed that they are not likely to get out of order or to wear objectionably during use.

A feature of the invention consists in a gripper mechanism comprising 2 carrier having a fixed jaw and a cam, combined with a closing bar having a jaw pivoted thereto between its ends to be moved downwardly by the bar and rocked by the cam. This invention is herein shown as embodied in a grippers mechanism in which the jaws are closed by a movement of the operating bar in one direction, and are uplifted for pulling the upper by a movement of the gripper carrier, together with the operating bar, in the opposite direction. The movable jaw is formed as a lever directly pivoted to, or fulcrumed upon, the operating har substantially midway of its length and having its upper end formed to engage, and be rocked by, the cam mounted in the gri per carrier. A spring is preferably employs for holding the upper arm of the movable jaw continuously against the cam and, as illustrated, provision is made for adjusting the cam to vary the point in the movement of the operating bar at which the closing shall be effected. The com is shown as detachably connected to the gripper carrier so that it can be removed and replaced by a cam of different shape for giving a different closing movement to the lpivoted jaw. These and other features of t e invention will be fully explained in connection with the following description of the referred embodiment of the invention whicli is shown as a gripper adapted for use in the hand method t 110 of la ting machines, an example of which is shown in United States Letters Patent No. 584,744, granted June 15, 1897.

Figure 1 is a side elevation, partly in section; Fig. 2 is a similar view showing the jaws closed.

The gripper carrier or shank 2 has a boxlike extension 5, the inner wall of which supports a cam. This cam, while it might be formed as a. surface upon the inner wall of the extension 5, is herein shown as a. plate ('5 having a jaw closing surface 7 and adapted, by means of the screw-threaded extension 8 and locking'nuts. to be adjusted for varying its relation to the grippers jaws. One side face i of the extension 5 is shown as removable to give convenient access to the interior of the cam box for permitting the removal of the cam and the substitution of a cam of difl'erent shape, if that is desired; this also permits a worn com to be replaced. The lower end of the extension is formed as a clamp within which is secured the rigid griplper jaw 10 of usual construction.

'1 e operating bar 12 is arranged to be re ciprocated endwise in the tubular portion of the gripper carrier 2 and to the lower end of vthe bar is directly pivoted the movable jaw 15 of the grippers. This jaw is formed as a lever with the ivot oint or fulcrum 14 located substantia ly mi way between the ends of the lover. The upper end of the lever is extended laterally toward the cam plate 6, 7, and may be provided with a. roll to form a non-wearing contact with the cam. A spring operating against a lunger 18 is arranged in the bin-12 to hold t e upper arm of the jaw lever 15 against the gripper closing cam.

n the use of the gri pers, the jaws are closed by the downward movement of the bar 12 which carries the jaw 15 toward the jaw 10 in a path determined by the formation of the cam. first to embrace and then to seize the stock. As shown, the cum has a substantially straight surface at its upper end and an oblique surface near its lower end and this formation causes the jaw 15 to follow a path substantially like that indicater] by the dotted line which connects the tips of the two jaws in Fig. 1. In opening the grippers, the spring plunger 18 holds the upper arm of the jaw lever 15 against the cam, thus preventing any loose movement of lever 15 and insuring that the jaws will stand separated, as shown in Fig. 1, while the operating bar is raised. A powerful leverage for gripping the stock against the jaw 10 is provider by the arrangement as will be a prcciated from examination of Fig. 2. he gripper carrier is formed with a ball head y which the grippers are uplifted for pulling the stock as described in said atent. One merit of this construe tion is onnd in the simple design and strong form of the comparatively few elements comprised in the mechanism and another advantage is found in the provision for adjustment to vary the movement of the pivoted jaw and the opportunity to replace one jawclosing cam by anothercam.

Having explained the nature of this in vention, and fully described the preferred embodiment of the same, I claim as new and desire to secure by Letters Patent of the United States l. A gripper mechanism having, in combination, a carrier provided with a fixed jaw and a cam, and a closing bar having a jaw pivoted directly thereto substant-ia 1y midway between the ends of the jaw and arranged to be moved downwardly by the bar and rocked by the cam to embrace and grip the upper.

2. A. gripper mechanism having, in combination, a carrier provided with a fixed jaw and a cam, a closing bar having a jaw pivoted thereto substantially midway between the ends of the jaw and arranged to be moved downwardly by the bar and rocked by the cam, and a a ring mounted in the bar and arranged to mid the upper arm of the jaw continuously against the cum.

3. A gripper mechanism having, in com bination, a carrier provided with a fixed jaw and a cam, and a closing bar having a jaw pivoted thereto and arranged to be moved downwardly by the bar and rocked by the cam, said mechanism having pro vision for adjustment of the cam to vary the point in the downward movement of the bar at which the gripping of the stock will be effected.

4. A gripping mechanism arranged to be closed by force applied in one direction and to be actuated to pull the stock by force applied in the reverse direction, having, 1n combination, a carrier provided with a fixed jaw and a removable cam, and a closing bar having a jaw directly pivoted thereto midway between its en s to be moved downwardly by the bar and rocked by the cam.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

EDWARD A. S'ITIGGINS.

Witnesses:

CHANNING WHITAKER, J12, LEONARD M. JOHNSON. 

